view sip-in/sip_uas.c @ 124:7e04d28fae8b

sip-in: default use-100rel to no BulkVS servers act badly when we send a reliable 180 Ringing response to an incoming call, even though they advertise 100rel support in the Supported header in the INVITE packet, and we probably won't be implementing 100rel for outbound because doing per-the-spec PRACK as a UAC is just too burdensome. Therefore, we need to consider 100rel extension as not-really-supported in themwi-system-sw.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 01 Oct 2022 15:54:50 -0800
parents 0d6435808bcd
children
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/*
 * Basic UAS functions for themwi-sip-in.
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <syslog.h>
#include "../libsip/parse.h"
#include "../libsip/uas_basic.h"
#include "../libsip/out_msg.h"

static void
unsupported_method(req, ess, sin)
	struct sip_pkt_rx *req;
	struct uas_parse_hdrs *ess;
	struct sockaddr_in *sin;
{
	struct sip_msg_out resp;
	int rc;

	start_response_out_msg(&resp, "501 Method not supported");
	rc = add_resp_basic_headers(&resp, ess, req->req_method);
	if (rc < 0) {
too_long:	syslog(LOG_ERR, "sending 501 error: response length exceeded");
		return;
	}
	rc = out_msg_add_header(&resp, "Allow", "INVITE,ACK,PRACK,CANCEL,BYE");
	if (rc < 0)
		goto too_long;
	out_msg_finish(&resp);
	sip_tx_packet(&resp, sin);
}

void
process_sip_request(msg, sin)
	struct sip_pkt_rx *msg;
	struct sockaddr_in *sin;
{
	struct uas_parse_hdrs ess;
	int rc;

	rc = uas_get_basic_headers(msg, &ess);
	if (rc < 0) {
		syslog(LOG_ERR, "SIP %.16s request: bad or missing %s header",
			msg->req_method, ess.error_field);
		return;
	}
	/* dispatch by method */
	if (!strcmp(msg->req_method, "INVITE"))
		handle_sip_invite(msg, &ess, sin);
	else if (!strcmp(msg->req_method, "ACK"))
		handle_sip_ack(msg, &ess, sin);
	else if (!strcmp(msg->req_method, "PRACK"))
		handle_sip_prack(msg, &ess, sin);
	else if (!strcmp(msg->req_method, "CANCEL"))
		handle_sip_cancel(msg, &ess, sin);
	else if (!strcmp(msg->req_method, "BYE"))
		handle_sip_bye(msg, &ess, sin);
	else
		unsupported_method(msg, &ess, sin);
}